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Lalo Alvidrez December 17th, 2013 11:56 AM

Problem with audio on vx2100
 
1 Attachment(s)
I am having problems with the audio captured on my sony vx2100. I have two of them and they both seem to have the same problem. there will be audio clicks throughout a video I've captured. I've tried different tapes thinking I had a bad group of tapes but still happening. I uploaded a sample .Is this a common problem as the cameras get older? Does any one else have this problem

Greg Miller December 17th, 2013 04:44 PM

Re: Problem with audio on vx2100
 
I don't hear anything that I would call a "click" ... a sharp transient noise where there should be none.

I do hear (and see) a complete audio dropout from roughly 5.339 to 5.372 seconds. With this program material, I can't tell whether this represents (a.) a short bit of audio that is missing, or (b.) a brief bit of silence that was essentially inserted into the midst of the audio track without losing any of the audio data.

If you play back the tape on the camera itself, and listen on headphones, do you hear the same sort of dropouts? Or does analog playback seem correct without any gaps?

Lalo Alvidrez December 17th, 2013 08:35 PM

Re: Problem with audio on vx2100
 
1 Attachment(s)
I hear it as I'm recording and also when I play back on Sony Vegas. Here is another sample with more spots.
I called it a click put not really sure how to describe it, but I can also hear it during capturing. I did listen to it playing the tape directly in the camera and it can still be heard.

Derek Heeps December 17th, 2013 09:29 PM

Re: Problem with audio on vx2100
 
I have no direct experience with the VX 2100 , but I did use a VX 1000 for many years without experiencing that issue . Is this sound from the camera's built in microphone , or from an external mic plugged into the mini jack ? Mini jacks are flimsy connectors at best and can wear ; also sockets mounted on circuit boards have a habit of developing bad solder connections over time . If the mic input on these cameras runs through a ribbon cable these can give trouble too . Having said that it is unlikely both cameras would go wrong at the same time .

If you are hearing it during monitoring and the same external mic is being used with both cameras , I'd be looking at that first . With it being heard during recording , you can rule out tape dropout since there is no off-tape monitoring on these camcorders , you are just monitoring the input signal via the camera's electronics . Is there any other external equipment connected , such as an audio mixer or are you using a radiomic ? If you have an external audio source plugged in , is the camera moving when these clicks occur ( bad connection at the mic input ) ? Has this only occurred at one location , or numerous places ( external interference ) ? Are you using batteries or mains power ( mains borne interference ) ?

This needs to be investigated logically and carefully , the above are just a few things to look at , and what I have thought of in a few minutes - others may have additional ideas .

Derek Heeps December 17th, 2013 09:34 PM

Re: Problem with audio on vx2100
 
Just to add , if that sound is from the camera's on board mic , try plugging in an external mic and see if it makes any difference . If an external mic , try the built in one , or another one , and use different cables .

Lalo Alvidrez December 17th, 2013 11:17 PM

Re: Problem with audio on vx2100
 
Upon further troubleshooting I also noticed some, not as much, of the same audio glitches from the second camera which is a Sony PD170. Which has an external mic connected to it. The Vx2100 was connected to a sound board via 3.5mm to 6.35mm mono. Another vx2100 was being used at another venue and after reviewing the footage had the same problem. It was recording from the mic. Is it possible that it could be the tapes? that's the only thing they all had in common. BTW, they were all on battery power. I've experienced this in different venues, not just one particular one. May try the external mic to see if that works.

Warren Kawamoto December 17th, 2013 11:45 PM

Re: Problem with audio on vx2100
 
I don't think you would hear the problem if the tapes were causing the glitches during recording, but it sure does sound like tape glitches. Very perplexing.

Don Bloom December 18th, 2013 07:08 AM

Re: Problem with audio on vx2100
 
It is POSSIBLE that you got a series of tapes that MIGHT be causing this problem. when I shot tape I used one brand exclusively in my PDs for many years and once I got a batch of about 10 tapes (out of 100) that caused me a small problem similar to what you described. I was concerned of course so I even took my cams to my repair guy and he checked them top to bottom and found nothing wrong and everything was in alignment so I went to the "back" of the tape boxes, tried a different box of tapes and magically the issue disappeared. I took those "bad tapes" they are still sitting on my shelf.
Try some new tape stock and see if that helps. Might not hurt to use a head cleaning tape first though BUT follow the instructions to the letter or you could damage your cameras.

Greg Miller December 18th, 2013 10:50 AM

Re: Problem with audio on vx2100
 
Quote:

Originally Posted by Warren Kawamoto (Post 1824801)
I don't think you would hear the problem if the tapes were causing the glitches during recording, but it sure does sound like tape glitches. Very perplexing.

I have no experience with this specific camera. But I have to agree with Mr. Kawamoto. If you hear the dropouts when monitoring while you're in recording mode, I can't envision how the tape would be involved.

Don Bloom December 18th, 2013 01:29 PM

Re: Problem with audio on vx2100
 
Hmmm, I missed the part about hearing it as you're recording. Not tapes then. Maybe the heads are out of alignment? Weird, I've never heard this before.

Derek Heeps December 19th, 2013 07:36 AM

Re: Problem with audio on vx2100
 
I'm pretty certain the VX 2100 did NOT have off tape monitoring , ie 'confidence heads' ( like in three head open reel tape recorders ) , that feature is the preserve of professional units - the only video machine I have personally had with that feature was my old Sony VO 6800 U-Matic recorder .

The 2100 will only be offering 'E-E' monitoring , I'm fairly certain .

Marco Leavitt December 19th, 2013 09:58 AM

Re: Problem with audio on vx2100
 
It seems unlikely to me that two cameras owned by the same person would develop the same oddball quirk. I think your audio problems are happening before they get to the camera. I would change the audio setup completely (new cables, mics, everything) and do some test recordings. Borrow someone else's gear if you can. Bet something else is going on.

Rick Reineke December 19th, 2013 11:23 AM

Re: Problem with audio on vx2100
 
Why is the clip 44.1Hz and not 48K, which the camera would record? The glitches 'appear' to be digital dropouts, I can see no other artifacts in the waveform.. which a faulty cable/connector issue would leave some kind of residual noise. The fact it was audible during recording is confusing and would rule out a tape issue, as the camera allegedly has no 'read after write' off tape monitoring.
All the dropouts are the same length as well ( about 1,465 samples) Electrical glitches maybe?

In any case, it can easily be 'salvaged' using the Sound Forge Pro's 'Replace' tool which would not corrupt sync either.

Greg Miller December 19th, 2013 12:09 PM

Re: Problem with audio on vx2100
 
Rick, I agree with your analysis. They are surely digital dropouts.

As you say, puzzling if they were heard during recording since that's ahead of the tape generation. Perhaps that isn't really the case, maybe that's a mis-remembering of the actual scenario.

One question in my mind: was the audio muted for a few milliseconds, or were some blank samples inserted into the data?

If the former, there would be some missing audio, which could not be replaced.

If the latter, it could be repaired by cutting out the "zero sample" sections. Does the "Replace" tool do this automatically?

Rick Reineke December 19th, 2013 12:50 PM

Re: Problem with audio on vx2100
 
"it could be repaired by cutting out the "zero sample" sections. Does the "Replace" tool do this automatically?"
- The Sound Forge Pro 'Replace' tool inserts the exact same number of selected time/samples using adjacent audio prior to the selected data. (in some instances, 'reversing' the data, replacing and re-reversing yields better results) The SF 'Overwrite' tool does the same with user copied data. Neither works perfectly 100% of the time.. it depends on the material.. and some skill of course.


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